A aby mně někdo nenařknul, že si vymýšlím a nadržuju ;o), tak tady je jeden článeček, kterej z těch co mám asi nejlíp popisuje sekvenci událostí.
Důležitý bod jsem zvýrazil. Alpha floor protection je tam od toho, aby přesně takové situaci zabránil počítač. V daném režimu pak stačí jenom tahat za knipl (což řekněme člověk udělá instinktivně, když se lekne, nebo zjistí nebezpečí) a počítač automaticky zvyšuje výkon motorů, takže letadlo stoupe a nezvyšuje už dále úhel náběhu, nezávisle na tom, jak moc se za to tahá - nedojde tak k pádu a recovery je provedeno nejlepším možným gradientem.
Takže citát:
This accident was caused by human error on the part of many
people, including, but not limited to, the crew. The flyby of
Habsheim airfield was poorly planed and poorly executed.
Poor planning
No reconnaissance of the airfield was made by the Flight Division of
Air France in preparation for the flypast because of the extensive
experience of the pilots.
The crew were only given details of the flypast when they reported
for work on the morning of the flight. They were given no verbal
briefing on the display, or the airfield, which they were unfamiliar
with. According to the instructions given to the crew, which were
based on the invitation from the airshow organisers, the event was to
be aligned with runway 02. It was over this runway that they were to
perform a low, slow pass.
It was not until 450 feet AGL had been reached, on descent to the
airfield, that the pilot saw the crowd was along runway 34, not 02.
At this late stage in the descent he realigned the aircraft's path to
runway 34.
Poor execution
Habsheim airfield is located approximately 10NM north of the takeoff
point at Basle-Mullhouse Airport. The total flight time from takeoff
to impact at Habsheim was 4 minutes and 34 seconds.
Initially the crew climbed to 1000 feet AGL. Descent was commenced
5.5NM from Habsheim with the flight director set to Open Descent Idle
Mode, which held the autothrottle at flight idle. The engines
remained at flight idle until 5 seconds before impact with the trees.
The automatic system that might have prevented the crash, the Alpha
Floor function, was turned off by the crew as the aircraft descended
through 100 feet AGL, so that they could fly a slow speed, high angle
of attack, pass along the runway, without the engines automatically
throttling up as the maximum angle of attack was reached.
The rate of descent, with the engines at flight idle, as the aircraft
approached the airfield was still 600fpm, when the altitude was only
100 feet. The aircraft was levelled out by application of elevators
only, with the wheels 30 feet above the runway and the engines still
at flight idle. There were 40 foot high trees only 200 feet beyond
the end of the runway. When the crew recognised the trees full power
was applied. At this stage the aircraft was flying at only 120 knots
with an angle of attack of 15 degrees. The engines responded within
their certification guidelines, but approximately 5 seconds later the
aircraft impacted the trees.
The minimum altitude allowed by the French regulations for such
events was 170 feet AGL.
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